The reason why we pick up all fallen Apples here
is that they become a vector for the Coddling moth
to overwinter in the ground. If organic growers do
not want to spray for this insect then their number
one preventative is picking up the Apples as soon
as they fall on the ground.
If you want to really cut down the number of Apples
this tree produces just prune the heck out of it every
year. That way what Apples you do have will be of
better quality than a host of the other baking Apples
will be. If you want this tree to be an ornamental
flowering Apple instead then spray Gibberellic acid
(Ga3) about a week after petal fall. Naphthalene acetic
acid (NAA) is a more complete chemical thinner
applied at the same flowering stage. Both the above
are growth hormones and are not considered restricted
use pesticides.
You may want to read this article below.
Thinning Apples Chemically
Jim